I have both XFCE and Unity 7 running at the same time. XFCE uses the display :1 and U7 the display :0. If I switch from the u7 tty to the xfce tty xserver crashes and here's the backtrace:
(gdb) bt
#0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:58
#1 0x00007f34658a23ea in __GI_abort () at abort.c:89
#2 0x0000562392d1f53e in OsAbort ()
#3 0x0000562392d251d3 in ?? ()
#4 0x0000562392d25fbd in FatalError ()
#5 0x0000562392bf5246 in xf86VTEnter ()
#6 0x0000562392bb6f8d in WakeupHandler ()
#7 0x0000562392d15759 in WaitForSomething ()
#8 0x0000562392bb21ee in ?? ()
#9 0x0000562392bb6413 in ?? ()
#10 0x00007f346588b3f1 in __libc_start_main (main=0x562392ba0300, argc=11,
argv=0x7ffd2e525d08, init=<optimized out>, fini=<optimized out>,
rtld_fini=<optimized out>, stack_end=0x7ffd2e525cf8)
at ../csu/libc-start.c:291
#11 0x0000562392ba033a in _start ()
--------
Xserver version:
$ Xorg -version
X.Org X Server 1.18.4
Release Date: 2016-07-19
X Protocol Version 11, Revision 0
Build Operating System: Linux 3.13.0-95-generic x86_64 Ubuntu
Current Operating System: Linux tiktok 4.8.0-26-generic #28-Ubuntu SMP Tue Oct 18 14:39:52 UTC 2016 x86_64
Kernel command line: BOOT_IMAGE=/boot/vmlinuz-4.8.0-26-generic root=UUID=045392ae-75f8-47cf-9645-43be94987e8e ro quiet splash vt.handoff=7
Build Date: 07 September 2016 05:11:52AM
xorg-server 2:1.18.4-1ubuntu6 (For technical support please see http://www.ubuntu.com/support)
The Xorg.0.log doesn't show any errors.
---
.tmp.unity_support_test.0:
ApportVersion: 2.20.3-0ubuntu8
Architecture: amd64
BootLog:
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
DistUpgraded: Fresh install
DistroCodename: yakkety
DistroRelease: Ubuntu 16.10
DistroVariant: ubuntu
DkmsStatus:
tp_smapi, 0.42, 4.4.0-45-generic, x86_64: installedError! Could not locate dkms.conf file.
File: does not exist.
tp_smapi, 0.42, 4.8.0-26-generic, x86_64: installed
ExtraDebuggingInterest: Yes
GraphicsCard:
Intel Corporation HD Graphics 5500 [8086:1616] (rev 09) (prog-if 00 [VGA controller])
Subsystem: Lenovo HD Graphics 5500 [17aa:2226]
InstallationDate: Installed on 2016-03-15 (246 days ago)
InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
MachineType: LENOVO 20CMCT01WW
Package: xorg-server (not installed)
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.8.0-26-generic root=UUID=045392ae-75f8-47cf-9645-43be94987e8e ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 4.8.0-26.28-generic 4.8.0
Tags: yakkety ubuntu compiz-0.9
Uname: Linux 4.8.0-26-generic x86_64
UnreportableReason: The report belongs to a package that is not installed.
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip kvm libvirt libvirtd lightdm lpadmin plugdev pulse pulse-access sambashare sudo vboxusers
_MarkForUpload: False
dmi.bios.date: 04/06/2015
dmi.bios.vendor: LENOVO
dmi.bios.version: N10ET33W (1.12 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20CMCT01WW
dmi.board.vendor: LENOVO
dmi.board.version: 0B98417 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrN10ET33W(1.12):bd04/06/2015:svnLENOVO:pn20CMCT01WW:pvrThinkPadX250:rvnLENOVO:rn20CMCT01WW:rvr0B98417WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.name: 20CMCT01WW
dmi.product.version: ThinkPad X250
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.13.0+16.10.20160818.2-0ubuntu2
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.70-1
version.libgl1-mesa-dri: libgl1-mesa-dri 12.0.3-1ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 12.0.3-1ubuntu2
version.xserver-xorg-core: xserver-xorg-core 2:1.18.4-1ubuntu6
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.2-1ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.7.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160706-1ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-2
run apport-collect 1640146